Osiris completes major routine maintenance and inspection works at EDF Energy Sizewell B nuclear power plant.

Osiris, a part of James Fisher and Sons, combines multi-skilled personnel and capabilities to provide an integrated solution for inspection, repair and maintenance at EDF’s Sizewell B nuclear power plant.

During a scheduled maintenance outage, which takes place every 18 months, Osiris carried out inspection works, which required diving and ROV capability to complete the project within a narrow time scale and within budget.

The scope varied from routine inshore air diving inspection work of the cooling water intake heads, to the maintenance and cleaning of the drum screens and chambers, which filter sea water used on the main turbine condensers and reactor ancillaries.    

Osiris also provided additional personnel to support the works on a standby basis during the scheduled outage for potential diving contingency, vital within the Radiation Controlled Area (RCA). This required additional medical certification and advanced training to make sure the team entered the RCA area safely.

Inspections were required on an intake culvert which connects the intake heads to the drum screen chamber, which extends 800 metres. To complete this, Osiris had to provide a bespoke solution by upgrading the current capability of the Falcon ROV, which saw the installation of a light weight fibre optic cable, allowing the Falcon to travel up to 850 metres. This provided operational flexibility and manoeuvrability when carrying out the detailed inspection work, due to the cable being lighter.

The project took place within a potentially high risk environment, but through the use of appropriate mitigation measures, Osiris was able to deliver a safe, compliant solution. Aiden West, managing director for Osiris, highlighted the well-handled safety concerns within the project, “Diving within itself can be dangerous when incorrect preparation takes place, but when the dive site is inherently more dangerous than normal circumstances, cooperation by all parties involved is paramount to make sure a routine piece of inspection work is carried out successfully. Our capability is underpinned by our team and we operate to the highest of industry standards and with the combined efforts of the team at EDF Sizewell B, we were able to complete the project safely, on-time and within budget."